Method for preparation of emulsion type pigmented metal drawing compounds



na -aw 54 Dec. 20, 1960 W. METHOD FOR PREPARATION OF EMULSION TYPEPIGMENTED METAL DRAWING COMPOUNDS Filed Oct. 8, 1954 BRENNAN ET AL .2

AGITATE WATER, HYDROPHYLL/O GELLING AGENT a PIGMENT TO PRODUCE A SMOOTHPASTE ADD FATTY ACIDS 6 AGITATE TO PRODUCE A FLUFFY LIGHT DISPERSIONGRADUALLY ADD WITH STIRRING OAUSTIC SODA 8 WATER ASA SOLUTION TO PRODUCEA SMOOTH ELASTIC-LIKE MASS CUT BACK WITH MINERAL OIL 8 FATTY OIL (EITHERONE FIRST) TO PRODUCE FINAL PRODUCT OF DESIRED OONSISTENCY IN V EN TORS.

ELMER W. BRENNAN BY ERNEST TI FRONCZAK THOMAS W.

MARTINEK Jarromvsv United States Patent METHOD FOR PREPARATION OFEMULSION TYPE PIGMENTED METAL DRAWINGCOM- POUNDS Elmer W. Bre'nnan,Carpentersville, and :Ernest Fronczak and Thomas WPMartinek, CrystalLake, 111.,

assignors to The Pure Oil Company, Chicago, 111., a

corporationof Ohio Filed Oct. 8, 1954, Ser. No. 4'61Qll52 Claims. (CL252-18) This invention relates to a m'ethodfor the preparation of metalworking lubricants. More particularly, this invention relates to aprocess for the preparation of nonsettling, pigmented drawing andcuttinglubricants.

Metal-working machinery, particularly machinery utilizing dies, diepresses and the like to shape, 'cut or otherwise finish metal parts,requires satisfactory lubricants during metal-working operations,requirements of the machinery depending upon a number of factors.Lubricants which have been used in the past to protect both the workingmachinery and the metal 'beingworked "have become complex as faster andlarger operations on metals :more difiicult to work have come to thefore. Changing techniques have necessitated better lubricants.

In general, metal-working processes involving the use of dies can bedivided into two main categories, cutting of shearing operations andshaping or forming operations. Cutting or shearing processes may consistof any one or more of the following types of operations: piercing,punching, perforating, blanking, shaving, notc'hing, shearing, trimmingand sprue-cutting. Shaping operations may include a number ofsub-classes such as bending, curbing or Wiring and seaming, drawing, andcompressing or squeezing; moreover, drawing operations which comprise alarge proportion of the total die-utilizing, metalworking operations maybe divided into such types as surface finishing or sizing, forging,riveting, swagging, upsetting, bull-dozing, stamping and extruding.

As mentioned above, metal-working lubricants vary according to theconditions of operation but in the main may be divided into five typesof cutting and drawing or shaping lubricants. These are the following:water emulsions of soluble oils; soluble pastes with water; straightmineral oils or compounded oils; pigmented lubricants; and, sulfurizedand/or chlorinated oils and bases.

In general, a metal-working lubricant (or a lubricant for cutting andshaping, -or drawing) is designed to prevent the metal being worked fromsticking to the die or seizing the tool. The lubricant is also presentto assist the flow of metal so as to prevent scratching or breaking ofthe piece being worked and to afford maximum life to the die by reducingabrasion and heat generation and by dissipating heat when present.

It has been found that plain mineral oils do not possess the requisitephysical characteristics necessary for .good lubricants in modernmetal-working operations because film strength andadhesivecharacteristics are notably deficient in most straight mineraloil lubricants used for this purpose. A number of types of fattymaterials, such as beef tallow, degras, lard oil and castor oil havebeen used in the preparation of pastes for metal-working lubricants inattempts to overcome these drawbacks of mineral oil. Castor oilparticularly is extensively used because of its high film strength, lowcoefficient of friction and good wetting powers. I I

Fats and solids also have been utilized as lubricants formetal-workingoperations, including modifications re- .Sulting from saponification,chlorination, sulfurization,

ICC

and emulsifi'cation, and combinations thereof with light mineral oilswith or without active sulfur. Tests have shown that film strength is avery important characteristic "of metal-working lubricants and that saidfilm strength at "either a liquid or paste lubricant may be measurablyincreased by the introduction of certain solid materials in variableamounts, such as 20 to 35 percerit. The function ofsuch a solid is tomaintain the oily fil'rn on 'the work metal and to prevent seizure ofmetal to rn'etal.

Recently, solids such as natural calcium carbonate (chalk), leadcarbonate, lead oleate, zinc oxide, barium carbonate, lithopone, 'talcand graphite have been frequently used. Some of these solids are alsowell-known pigments. Compositions incorporating such solids with one ormore lubricating agents such as oils and fats have been frequentlyutilized in drawing and stamping operations. For light drawingoperations in the past, simple compounds such as sodium stearates have"been used, but heavy drawing operations have been found to requirelubrication by compositions of a more complex "nature, for example,sodium s't'earate in combination "with chlorinated mixed acids andsulfurized fatty oils.

When 'a metal is drawn, it is forced through a hard steel die and takesthe shape imposed upon it by the configuration of the die. Thisdeformation involves high pressure between the surface of the metal andthe die, and high surface temperatures are generated. If lubrication ispoor in the areas where high temperatures and pressures are found duringthe drawing operation, adhesion of the worked metal to the surface ofthe die causes bad scratching and tearing of the surface of the drawnarticle, and necessitates refacing the die because of abrasion. Thetemperatures generated at the metaldi'e interface may be so high that .adefinite welding effect or alloying may occur and the worked metal andthe die fuse. Such an occurrence necessitates rejection of the metalbeing worked and refinishing of the die, so that valuable time and laborare lost and operation costs are greater. Such welding might evenrequire replacement of the die at great expense. Drawing compoundsacting as lubricants must be designed to withstand the extreme pressureand temperature conditions encountered in the drawing operations. Asuitable drawing lubricant operates not only to reduce friction betweenthe die and metal being worked so as to reduce the amount of seizure,pick-up and welding, but also serves to cool the item being worked toprevent undesirable metal expansion and reduced precision, If properlycompounded, a drawinglubricant can significantly reduce operation costs.

Stamping operations are somewhat different from drawing operations butrequire, in general, similar lubricants. in stamping operations, themetal is not squeezed but merely bent itno the appropriate shapes,designs and configurations. In stamping operations, as with drawingoperations, high pressures and temperatures are present at the die-metalinterface and seizure, welding and allied phenomena are prevented onlyby the judicious use of an appropriate lubricant which reduces frictionand thereby reduces temperatures generated during the proces's. Heavy,s'ulfurized base oils blended with various preparations of light mineraloil have been mainly used, as has been the case in drawing and othermetalworking operations.

The die presses used during drawing operations "may be of non-hydraulicor hydraulic varieties and generate pressures as high as 1,000 tons ormore. Metals of Ipractically all types may be worked in die presses,metals which have a low elastic limit compared with ultimate strengthbeing particularly desirable for deep-drawing operations. open hearthsteel with a low carbon content,

foi j example about 0.05-0.08 percent, is suitable for de ep 1 workingoperations are conducted depend upon the metals .beingworked and thecharacteristics ofthe metal dies. for instance,brass can be drawn onmetal dies at speeds lot the press crankpin as great as 2,000 feetperminute;

steel, however, may be drawn on steel dies at only about 35 to -60- feetperminute. The rate of production of drawn stainless steel is evenlower, as is that of magnesium.. t

Drawing and stamping lubricants are applied directly to the sheets orstrips of metal by the use of a brush, swab, felt pad or by spraying,dipping or passing between lubricated rolls. It has been found that thelatter method .of applying lubricants to the working material is themost economical and satisfactory in that a uniformly-thin, lubricatingfilm is deposited which either disappears during the drawing operationor may be easily removed after ,the drawing operation by a suitablewashing procedure. In general, it is seen that a satisfactory lubricantfor metal-working operations must have extreme pressure qualities,thermal stability, and high lubricating qualities. As aforementioned,newer, multi-purpose, metal-working lubricants have been compoundedprimarily of a number of fatty substances and incorporate pigmentswhich, in appropriate amounts, tend to increase the extreme pressurecharacteristics and prevent seizure of metal to metal. Difficulties,however, have been encountered with these prepared compositions due tothe fact that the pigment component of the composition settles out overvarious periods of time, especially when the composition is .cut bac orreduced in concentration by dilution with water or oil prior to its use.It has been further noted that some 'of the most successful types ofmetal-working lubricants 'of the pigmented variety are water-solubleemulsions, which afford ease of application and some degree ofstability. Where the pigment component of such a desired compoundedcomposition proves to be difficult to keep in suspension, the degree ofprotection against extreme pressure and rust afforded duringmetal-working operations is indeterminable. Vacillation in theefficiency of the metal-working operations may occur, increasing costs.

Heretofore, the lubricating qualities of pigmented lubricants havevaried from satisfactory efiiciency, when freshly prepared pigment isuniformly suspended, to various degrees ofinefiiciency depending uponthe amount of pigment suspended at the time'the lubricantisuscd."Attempts to render pigmented, metal-working lubricants completelystable without laborious and costly milling procedures after thelubricant has been prepared have been largely unsuccessful.

' Accordingly, it is an object of this invention to provide a processfor the preparation of a suitable metal-working lubricant.

It is a further object of this invention to provide a method for keepingin suspension the pigment component of a pigmented metal-workinglubricant without milling the prepared product.

It is still a further obiect of this invention to provide a method forthe preparation of a pigmented, metal-working lubricant, particularlysuitable for drawing and stamping operations, which is homogeneous andstable without costly milling.

It is still another object of this invention to provide a pigmented,metal-working lubricant which is homogeneous and stable when dilutedwith water or oil.

Other objects and advantages of this invention will hereinafter bedisclosed and will be obvious to one skilled in the art. p

The accompanying drawing is a diagrammatic illustration of the stepwiseprocess of our invention.

Ingeperal, ourinvention comprises a processfor preparing a metal-workinglubricant. More particularly, our

invention comprises a method for the preparation of a pigmented,metal-working compound which is stable and homogeneous on dilution witheither water or oil. A particular point of novelty of our invention isinvolved in the order of addition of the compounds during thepreparation of the pigmented lubricant which obviates the necessity ofmilling or otherwise homogenizing the product in order to keep thepigment component of the com-1 position in stable suspension.

.The lubricant composition is preparedby the following process: A pasteof a major amount of water, a waterswellable, gel-forming compound, suchas bentonite, and a pigment compound, such as calcium carbonate, isprepared in a kettle. Fatty acids are then added to the paste, and afterappropriate stirring, a solution of caustic soda in water is added withagitation. As a final step, mineral oil boiling in the lubricating oilrange and lard oil are added. A typical final composition utilizing thisprocedure is the following: TABLE I Components Weight Percent Waterinitially added 29. 34 Bentonite, 325 mesh 1. 50 Precipitated CalciumCarbonate--- 21. 99 Au! nal Fatty Acids 10.79 Caustic Soda (98 percentAssay) 1. 49 Water subse quently added 5. 00 200 Viscosity Neutral Oil11.19 Bright Stock Extract"- 4. 81 Lard Oil 13.89

The product is homogeneous and the pigment suspension is stable evenupon dilution with equal parts of 'water or oil. This product is indirect contrast with the usual pigmented drawing compound of paste formwhich shows settling of the pigment on brief or long standing of saidlubricant so that a hard pigment cake is formed at the bottom of thecontainer when the compound is cut back with water.

The steps of the process of our invention will now be described in moredetail. The initial step involves the preparation ofa suitable paste.This paste may be made with variable amounts of water, bentonite orother hydrophilic, gel-forming inorganic and organic compounds, such asmontmorillonites, bentones, carboxy methyl cellulose, gelatins, etc.,and asuitable pigment. Bentonite is the preferred hydrophilic gellingagent. It has been found that the hydrophilic gelling agent and thelubricating pigment should usually have a mesh number of at least3 25 inorder to provide rapid dispersion and preferably should be of a finerparticle size, such as 0.1 micron. Granular and larger than 325 meshbentouite can be used but requires a longer time for proper dispersion.The physical and chemical state of the pigment should be that normallyprovided by the precipitation of the technically pure compound. Forinstance, 325 mesh limestone would not sufiice, since cementitiousmaterial therein prevents proper dispersion; 325 mesh precipitat'edcalcium carbonate would be suitable. In general, the finer the bentoniteand pigment particles the more rapid the pigment disperses, and the morestable and homogeneous the lubricating composition. Instead of calciumcarbonate, other suitable compounds may be used as pigments, e.g., leadcarbonate, zinc oxide, barium carbonate, lithopone, talc and graphite.In the case of pigments which are unprecipitatable, particles at leastas small as mesh size 325 would be satisfactory for the purpose of theinstant drawing composition. Any pigment which is used in the paint artas a pigmenting agent is suitable, provided it is of the requiredparticle size as defined above. ,Any such suitable paint pigment is described in the appended claims by the term particulate 'decylic, andarachidic acids.

pigment. The amount of water utilized in the preparation of the pastemay vary from that which isenough to convert the mixture from a cake toa paste to that which produces a paste of low viscosity. A medium-thickworkable paste is preferred.

The paste comprising a major amount of water, bentonite (or suitablesubstitute), and pigment may be prepared in any suitable manner, such asby mixing in an open, grease-type kettle with the use of suitablestirring means, such as a rotaryor paddle-type stirrer, etc., or aLightnin Mixer. Preferably, the bentonite or other hydrophilic gellingagent is added to the water to form a slurry or gel which is agitatedfor a time sufficient to thoroughly disperse the bentonite in water,after which the pigment is slowly added. The slurry is agitated orworked until a paste having a smooth consistency is formed.Alternatively, but less preferably, the water, gelling agent, and thepigment may be mixed simultaneously and agitated until the pasteformed'is ofa smooth consistency.

Animal fatty acids are then added to the paste in the kettle and theresulting mixture is agitated until homo geneous. The animal fatty acidsare those which are derived from beef tallow or other animal sources andcomprise, in general, unsaturated and saturated fatty acids, preferablya mixture of acids of 12 carbon atoms or more. Suitable fatty aclds are,for example, oleic acid, stearic acid, and the like. A typical mixtureof such .fatty acids has the following characteristics:

. TABLE II Percent free fatty acid (as oleic acid) percent 97-100 Acidnumber 192-204 Saponification number 196-207 Color 3 NPA Titer C.) 39-43Iodine value 50-60 Moisture, insolubles, and

unsaponifiables percent max" 3 Fatty acids other than animal-derivedfatty acids may be used, such as those prepared synthetically and thoseobtained from vegetable matter, such as soya beans, castor beans, rapeseed, etc. Further examples of suitable fatty acids, saturated andunsaturated are the following: hypogeic acid, elaidic, erucic,brassidic, behenic acid, linoleic, palmitolic, stearolic, behenolic,lauric, tridecoic, myristic, pentadecanoic, palmitic, margaric, non- Theamount of fatty acids added may vary. It is an object to producesufficient soap in situ in the composition by reaction of the fattyacids with alkali metal hydroxide to emulsify the other ingredients.Accordingly, enough fatty acids may be added for a final soapconcentration of about 5 weight percent to about 25 weight percent.Moreover, the final composition may contain free unreacted fatty acidsup to about weight percent or more, but about 1.5 weight percent ispreferred; such free fatty acids act as a lubricity agent in thecomposition.

It should be noted that after the addition of the fatty acids to themixture inthe kettle, the batch is transbefore the aforesaid addition,but upon addition of the caustic solution, the light and fluffydispersion gradually begins to become sticky and rubber-like inconsistency. The caustic solution is followed by a variable amount ofwater which has been used to wash the container in which the causticsoda and water have been mixed. As agitation of the mass continues, thecurds disappear and the mass becomes auniformly smooth, somewhatelastic, sticky paste. Certain other alkali metal hydroxides may be usedin lieu of caustic soda, for example, potassium hydroxide. In fact, anybasic or alkaline substance which will react with the fatty acidspresent in the mixture to form water-soluble organic salts orwater-soluble soaps may be utilized. The amount of alkaline reagentadded is that which is necessary to react with the fatty acidsaforementioned to produce in situ the emulsifier or soap in an amount ofabout 5 weight percent to about 25 weight percent. The alkaline reagentmay be present in amount sufficient to react with all or some of thefatty acids or may be present in a small excess without deleteriouslyaffecting the composition. That is, the final composition may be acidic,neutral or slightly basic.

The fourth step involving the addition of mineral oil and fatty oil tothe aforementioned smooth elastic mass to produce a desired viscosity inthe final product may proceed rapidly; it is of no importance whetherthe'fatty oil is added before or after the mineral oil or togethertherewith. Any fatty oil, such assperm oil, tall oil and the like, maybe added in appropriate amounts to produce a satisfactory product whenpresent in the mixture with mineral oils, but lard oil is the fatty oilpreferred because of its satisfactory lubricity and low cost. Themineral oil added to the composition in. the fourth step of the processof our invention may be any mineral oil boiling within the lubricatingoil range. This includes any single component or combination oflubricating oils and extracts thereof. An example of a suitablecompounded oil is 200 viscosity neutral oil blended with phenol extractfrom the manufacture of bright stock to an appropriate viscosity.Fractions obtained by extracting mineral lubricating oil with phenol,sulfur dioxide or other solvent commonly used for such purposes may beutilized alone or in combination; such extracts are obtained from themanufacture of bright stock and neutral lubricating oils. Thelubricating oil fractions abovementioned may be of high, medium or lowviscosity and be bright stock or neutral oil. Instead of having bothfatty oil and mineral oil added in the final step, one of these oils maybe eliminated and the other oil used exclusively; that is, .theproportions of mineral oil and fatty oil in the mineral. oil-fatty oilcombination may each vary from 0 to percent. After the addition of thefatty oil and mineral lubricating oil, agitation is continued until ahomogeneous, smooth paste is obtained which is then withdrawn tosuitable containers. This lubricant composition is economical, easy toprepare, efiicient in operation, and, when out back with an equal amountof water or oil, gives satisfactory results without pigment settling oroil separation.

The light and fluffy mixture obtained by the addition of fatty acids tothe slurry of water, calcium carbonate, and bentonite is unusual andunexpected, as is the rubbery, sticky mixture resulting from theaddition of caustic solution. Upon cutting back the 'finished compoundwith an equal amount of 200 viscosity neutral oil, a smoothnon-bleeding, homogeneous paste With similar consistency to the originallubricating compound is obtained. Likewise, dilution with an equalquantity of water results in a homogeneous liquid which shows no sign ofpigment separation within a 72-hour test period.

When a similar composition is prepared, but not in the particular andcritical order of addition specified in the process of this invention,similar dilution with oil results in slight oil separation, whilesimilar dilution with water produces an upper liquid phase and a lowersuspension phase. This pigment-suspension phase occupies about one halfof the volume of the reduced compound and decreases the utility andeffectiveness of the lubricant.

Example 1 A non-limiting example of the process of our invention is asfollows. Fifteen pounds of 325-mesh bentonite are dispersed by aLightnin Mixer in 35.23 gallons of water to form a slurry which then istransferred to an open-type grease kettle and agitated for an additional1-1.5 hours to assure satisfactory dispersion and suspension of thebentonite in the water. At the end of this time, 219.9 pounds of CalceneNC, a commercial, precipitated calcium carbonate of approximately 0.1micron particle size, is charged to the kettle and the slurry isagitated with a paddle-type stirrer until a smooth white paste isformed. Then 107.9 pounds of animal fatty acids derived from beef talloware added and the resulting mixture is worked until it presents a smoothhomogeneous appearance. The fatty acids are principally saturated andunsaturated acids of more than 12 carbon atoms, and have the followingcharacteristics:

percent 2 A gradual transformation from the smooth, thick, white mass toa very light, flufiy, curdy-looking paste occurs concomitant with avolume increase of approximately 50 percent. A caustic solution of 14.9pounds of caustic soda and 5.0 gallons of water is then prepared andgradually added to the kettle, with stirring, followed by one gallon ofwash water. The contents in the kettle gradually become rubbery andsticky, but as agitation continues, the mixture becomes smooth andsomewhat elastic in character. This smooth product is then mixed with ablend of 15.26 gallons of 200 viscosity neutral mineral oil and 5.91gallons of bright stock extract. After the mineral oil blend has beenadded, 138.9 pounds of a commercial lard oil (Larex No. 5) is added insmall portions to produce approximately 1,000 pounds of finishedproduct.

Numerous experimental processing procedures other than that of Example Iwere tried in making drawing compounds of the two similar compositionsshown in Table IV following.

TABLE IV Composi- Composi- Constituents tion A, Wt. tion B, Wt.

Percent Percent Animal fatty acids 10; 2 9. 2 Caustic soda (98%assay) 1. 45 1. 5 500 viscosity mineral lubricat n 16.0 16. Lard Oil(Larex 13.0 13. 9 Water 34. 35 34. 4 Calcene NC 1 22.0 22.0 Bentonite(325 mesh). 1.5 1.5 Soda soap, resulting in animal fatty acids andcaustic soda 11. 0 11.0 Free fatty acids, remaining after animal fattyacid-caustic soda reaction; 2. 5 1. 5 (average) (average) 1 Commercialprecipitated calcium carbonate.

Composition A was prepared by the following procedures:

TABLE v 8 reacted with the aqueous caustic soda solution and worked to asmooth paste.

Samples of the above preparations of Composition A were cut back in aseries of tests with equal amounts of 5 mineral oil and in a parallelseries of tests with equal amounts of water; results appear below.

TABLE VI 10 Sample Characteristics on oil cut-back Characteriscs m watercut-back A1 mealv appearance pigment settled. A2.-- o D0. A3 mealyappearance, but better than D0.

A1 and A2.

Settling was determined for a 72-hour period Composition B was preparedby the following procedures: TABLE VII (B1) A paste was made by mixingtogether all ingredients except the carbonate. Dry carbonate was thenworked in to form a smooth paste.

(B2) A slurry of water, bentonite, caustic and carbonate was made, towhich was added, in order, the fatty acids. lard oil and mineral oilswith stirring.

(B3) A slurry was made of bentonite, some of the water and 50 per centof the calcium carbonate. A paste was then made incorporating theremaining ingreclients with the exception of the lard oil. The lard oiland the slurry were then added alternately to the paste with stirring.

(B4) The procedure of (B3) was used, except that bentonite of particlesize finer than 325 mesh was utilized.

(B5) The fatty acids, caustic soda, lard oil and 50 percent of thecarbonate were mixed to form a paste, to which was then addedalternately the mineral oil and the slurry of bentonite, water and 50percent of the carbonate.

(B6) The same procedure as in (B5) was followed except granularbentonite of particle size larger than 325 mesh was used in place of the325 mesh bentonite.

(B7) The procedure of (B4) was followed, except that granular bentonitewas used instead of 325 mesh bentonite.

(B8) The procedure duplicated that of (B5).

(B9) A slurry of water, bentonite and calcium carbon- 7 ate was made inthe kettle to which was added progressively and in order the animalfatty acids, the caustic solution, the mineral oils and the lard oilwith appropriate stirring.

(B10) The procedure duplicated that of (B4).

(B11) The procedure duplicated that of (B9).

Samples of the above preparations of B Composition were cut back in aseries of tests with equal amounts of water and in a parallel series oftests with equal amounts of mineral oil. The results appear below:

smooth appearance very smooth appearanc Do. very slight separation.pignlignt settled.

do Do. do Do. very smooth appearance, no no pigment separation.

on separation. very smooth pigment settled. very smooth appearance, nono pigment separation.

oil separation.

v i The results indicate that only by the process of B9 (duplicated byB11) could a very smooth paste lubricant be prepared which remainedsmooth with no oil separation on being cut back with an equal amount ofmineral oil, and which showed no separation or settling of pigment overthe 72-hour test period when cut back with an equal amount of water. InB9 the steps of the process of our invention were followed in order toproduce the desired product. It is important that the lubricant exhibitsstability on being cut back with either oil or Water because manymetal-working operations are more efiiciently carried out with thelubricant thinned with water, and other metal Working operations demandgreater lubricity of the lubricating agent which is facilitated by theuse of a lubricant paste cut back with an oil rather than water.Complete flexibility of use may be achieved by preparing a pigmentedlubricant according to the steps of our process, the final compositionbeing satisfactory as a multi-purpose metal-working lubricant, smooth,homogeneous and stable towards pigment-settling without being milled.The usual type of pigmented drawing lubricant has to be finely milledafter compounding in order to hold the pigment in somewhat stablesuspension.

The equipment utilized in the process of our invention may be replacedby other appropriate equipment which would facilitate the process of ourinvention and which would be obvious to one skilled in the art.

We do not wish to be limited to a process for the preparation of adrawing compound, but clearly disclose that the lubricant prepared byour process may be effectively utilized as a lubricant in all types ofmetalworking operations, including cutting and drawing, stamping,punching, shearing, trimming and similar operations.

We claim and particularly point out as our invention:

1. A process for the preparation of a lubricant which comprises thesequential steps of admixing water with suflicient hydrophilicgel-forming particulate substance selected from the group consisting ofmontmorillonites, bentonites, carboxymethylcellulose, and gelatins toform a gelatinous slurry, mixing therewith sutficient particulatepigment, no larger than 325 mesh, to form a smooth paste, agitating themixture until a smooth paste is formed, adding to the paste an amount offatty acids having 12 to 24 carbon atoms per molecule, which whensaponified, will completely emulsify the final composition, mixing untila homogeneous mass is obtained, saponifying the fatty acids by additionof concentrated 10 aqueous alkali metal hydroxide solution, mixing thesaponified product with at least one oil selected from the groupconsisting of mineral oil boiling within the lubricating oil range andfatty oils, in an amount sufiicient to obtain a smooth, homogeneouspaste, and agitating the product until such paste is obtained.

2. The process in accordance with claim 1 in which the particulatepigment is selected from the group consisting of lead carbonate, zincoxide, barium carbonate, lithopone, talc, graphite, and calciumcarbonate.

3. A process in accordance with claim 1 in which said hydrophilicgel-forming particulate substance is a bentonite of approximately 325mesh.

4. A process in accordance with claim 1 in which said hydrophilicgel-forming particulate substance is carboxymethylcellulose.

5. A process in accordance with claim 3 in which said particulatepigment is calcium carbonate.

6. A process in accordance with claim 4 in which said particulatepigment is calcium carbonate.

7. A process in accordance with claim 3 in which said particulatepigment is zinc oxide.

8. A process in accordance with claim 4 in which said particulatepigment is zinc oxide.

9. A process in accordance with claim 5 in which said fatty oil is lardoil and in which said alkaline hydroxide is sodium hydroxide.

10. The process of preparing a lubricant paste that forms stableemulsions with oil and water comprising mixing approximately 29.34 partsby weight of water with 1.5 parts by weight of 325 mesh bentonite and21.99 parts of precipitated calcium carbonate until a smooth paste isobtained, adding 10.79 parts by weight of animal fatty acids, having 12to 24 carbon atoms per molecule, to the paste, and agitating until ahomogeneous mass is obtained, saponifying the mixture with concentratedaqueous caustic soda solution containing 1.49 parts by weight of causticsoda, and after saponification adding sufiicient mineral lubricating oilfraction and lard oil to give a smooth paste and agitating until asmooth paste is obtained.

References Cited in the file of this patent UNITED STATES PATENTS

1. A PROCESS FOR THE PREPARATION OF A LUBRICANT WHICH COMPRISES THESEQUENTIAL STEPS OF ADMIXING WATER WITH SUFFICIENT HYDROPHILICGEL-FORMING PARTICULATE SUBSTANCE SELECTED FROM THE GROUP CONSISTING OFMONTMORILLONITES, BENTONITES, CARBOXYMETHYLCELLULOSE, AND GELATINS TOFORM A GELATINOUS SLURRY, MIXING THEREWITH SUFFICIENT PARTICULATEPIGMENT, NO LARGER THAN 325 MESH, TO FORM A SMOOTH PASTE, AGITATING THEMIXTURE UNTIL A SMOOTH PASTE IS FORMED, ADDING TO THE PASTE AN AMOUNT OFFATTY ACIDS HAVING 12 TO 24 CARBON ATOMS PER MOLECULE, WHICH WHENSAPONIFIED, WILL COMPLETELY EMULSIFY THE FINAL COMPOSITION, MIXING UNTILA HOMOGENEOUS MASS IS OBTAINED, SAPONIFYING THE FATTY ACIDS BY ADDITIONOF CONCENTRATED AQUEOUS ALKALI METAL HYDROXIDE SOLUTION, MIXING THESAPONIFIED PRODUCT WITH AT LEAST ONE OIL SELECTED FROM THE GROUPCONSISTING OF MINERAL OIL BOILING WITHIN THE LUBRICATING OIL RANGE ANDFATTY OILS, IN AN AMOUNT SUFFICIENT TO OBTAIN A SMOOTH, HOMOGENEOUSPASTE, AND AGITATING THE PRODUCT UNTIL SUCH PASTE IS OBTAINED.